The present invention relates to asphalt compositions and more particularly to a unique asphaltic elastomer.
Asphalt is defined by ASTM as a dark brown to black cementitious material in which the predominating constituents are bituminens that occur in nature or are obtained in petroleum processing. ("Terms Relating To Materials For Roads And Pavements", ASTM designation D8). Asphalts traditionally have been used as protective films, adhesives, and binders, because of their waterproof and weather-resistant properties. Asphalt can be provided in a variety of forms as well as processed by a variety of techniques. These processing techniques include reduction, propane deasphalting, air-blowing, and the like. The resulting products can be catalytic asphalt, thermal asphalt, blended asphalt, asphalt emulsions, and the like.
Despite the apparent flexibility in processing asphalt into a variety of forms and products, one important asphalt-based product has eluded the art--asphalt elastomers. An elastomer for present purposes is a substance having the properties of natural, reclaimed, vulcanized, or synthetic rubber in that the substance stretches under tension, can have a high tensile strength, can retract rapidly, and can recover to substantially its original dimension. Often, elastomers are loosely called "rubbers". Because of the waterproof and weather-resistant properties of asphalt, an elastomer made therefrom would be a highly desirable product.
The present invention is addressed to such need in the art.